Combustion apparatus



LTSAQS H. TAYLOR March 25, 1930..

COMBUS T ION APPARATUS Filed Dec. l2, 1923 INVENTOR.

BY a7 @am M A TORNEY,

Patented Mar. 25, 1930- HUSTON TAYLOR, F DETROIT, MICHIGAN' .comsUs'rIoN Arranarus l Application led December 12, 1923. Serial No. 680,100.

This invention relates tothe construction of steam boilers especially adapted for liquid or gaseous fuels, and its object is to provide an internally fired, return-tubular boiler of this character with a combined furnace and iue of such small diameter that the combustion of the fuel of maximum efficiency is secured, and of such length that a maximum amount of heat can be transmitted to the surrounding water.

In the accompanying drawing,'Fi 1 is a longitudinal section of my improve boiler. Fi 2 is a vertical section on the line 2-2 of ig. 1. Fig. 3 is a section of a modified tyre of furnace. imilar reference characters refer to like parts throughout the several views.

The present boiler has a shell formed of the united cylindrical sections 1,2 and 3,

heads 4 and .5, sta '-bolts 6, 7 and 8 for bracing the heads, a steam dome 9 having an end 10, a rear breaching 11 to support the fire-brick deflector 12, fire-tubes 1 3 extending between the heads, a front breeching 14 onto which a smoke stack may be mounted, and a feed pipe 15 for the water to be evaporated,

having branches 16 to direct thethis pi water swn between the fire-tubes and the shell. The heads are shown formedl with thimbles 20 .to receive the ends of a substantially cylindrical member, the front end 21 of which is lined with refractory material 22, such as cylindrical sections, and the central and rear portion or flue 23 which is preferably circumferentially ribbed or corrugated. The furnace-flue lis uno structed throughout its length. l ,v

The eiiiciency of this boiler depends upon its peculiar. proportions. In a boiler recently lconstructed the fire-tubes are'fourteen feet long, the shell is four feet in diameter, the

furnace is eighteen inches in diameter, and

its combustion chamber is thirteen inches in diameter and about six feet long. Twentyof the original heat of the gases is ta six four-inch fire-tubes are used, as shown in Fig. 2. The length of the furnace-Hue is` preferably at least eight times the outside diameter of the furnace.

The injector 25 is connected to a source of fuel oil under pressure and a clear blue flame can be freely forced through the furnace-flue and back to the front through the L{ire-tubes. Under normal conditions this boiler evaporates about fifty per cent more water than boilers of the standard locomotive type and when necessary can-be pushed to evaporate one hundred per cent more, but under these conditions the boiler does not operate as economically.

I prefer to employ the muiiler 26 forv the incoming air as without the mufer the incoming air creates a roar.

The eiciency of this boiler is probably due to the smaller inner diameter of the lining of the combustion chamber or furnace which becomes very hot and causes complete combustion of the fuel before it passes from this furnace by reason of the intense reflected and radiated heat. In an event, this type ofboiler operates at an e ciency which the ordinary type of Scotch marine boiler with a large diameter furnace is incapable of attaining. The combustion of the fuel is practically instantaneous, resulting in a roaring plosions.

l sound because ofthe rapidly succeedingvex- The ra id rearward movement is somewhat chec ed by the time the gases reach the deilector 12 because the gases have given oi a large proportion of their heat which ac tion is facilitatedby the corrugations of the fluef23 which cause eddys to form in the gases as they move rearwardly and thus insure ref peated mixingj of the hotter inner and cooler outer gases. he gases rise and pass forward along the deflector 12 and pass forward through the fire-tubes 13, giving off heat in" the usual manner. But the great proportion en up bythe corrugated flue 23 and the unusual The'American Society of Mechanical En gineers in its boiler code has fixed eighteen inches as the maximum diameter of flues and as the minimum diameter of furnaces. The cylindrical member Which'receives the fuel is therefore a flue in the present construction. In furnaces of larger diameters, a vortical movement ofthe incandescent gases isusually sought for, but in obtaining this effect, the gases expand and thereby lose temperature. In the present case, the gases are forced rearwardly by the pressure of the fuel jet and as they give up their heat to the corrugated flue, these gases are compressed to bring up their pressure by the gases that folloW. In fact, the pressure of these gases is kept up until the breaching 11 is reached.

Gases are poor conductors of heat and therefore the conduit for the incandescent gases should be as small as possible so that the heat of the interior particles may readily pass to the Wall of the conduit. The velocity of the gases in such small conduits is high, which is very desirable as tests have shown that heat is taken up faster under such conditions.

No baille of refractory material against which fuel is .directed is necessary or even` desirable in the present boiler and the loss of heat incident to the use of such bafHes is avoided. The small cylindrical combustion chamber insures perfect combustion and the production of intensely hot gases which are driven at high velocity through the unlined portion of the flue.

The entire absence of soot and smoke in the unlined portion of the flue and in the firetubes, due to the complete combustion of the fuel in the lined or furnace portion, makes for great efficiency. This can be more readily sectional area, having an unobstructed bore, said bore being so proportioned that its radiant surface area of refractory material in square feet is approximately four or more l designed.

HUSTON TAYLOR.'

that the fuel is injected axially of and into v the hollow cylinder of refractory material Where it is immediately gasiied, and, as it is-already mixed with the proper amount of air, it practically explodes and the resulting gases are at the intense heat of explosion.

If desired, the combustion chamber may be formed as shown in Fig. 3, Where the metal furnace 30 is also lcorrugated and the refractory lining 31 conforms thereto.

The details of construction and proportions of the parts may all be changed by those skilled in the art WithoutA departing from the spirit of my invention as set forth in the following claim.

I claim In combination an elongated tubular refractery combustion flue of restricted cross- 

